<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta http-equiv="X-UA-Compatible" content="ie=edge" />
    <title>后盾人</title>
  </head>
  <body></body>
  <script>
    let user1 = {
      name: "李四",
      key: Symbol()
    };
    let user2 = {
      name: "李四",
      key: Symbol()
    };
    let grade = {
      [user1.key]: { js: 100, css: 89 },
      [user2.key]: { js: 35, css: 55 }
    };
    console.log(grade[user2.key]);
  </script>
</html>
